The Karyotypes of Seven Species of Tilapia (Teleostei: Cichlidae)

Abstract

The karyotypes of seven Tilapia species were determined from fin biopsies. Five species (T. congica, T. guineensis, T. macrochir, T. galiaea and T. andersonii) have 2n=44 comprising two double-length stt pairs and 40 smaller chromosomes, mostly stt. T. mariae has 2n=42 and T. sparrmanii 2n=40 with respectively 1 and 2 double-length in pairs. Differences in arm ratio in the group of smaller chromosomes were also noted between most species.